Photographic composition element and process

ABSTRACT

PHOTOGRAPHIC DEVELOPING AGENTS WHICH ARE ANHYDRO DIHYDRO HEXOSE REDUCTONE SILVER HALIDE DEVELOPING AGENTS PROVIDE LOW STAIN AND IMPROVED STABILITY WITHOUT UNDESIRED SENSITOMETRIC PROPERTIES IN DEVELOPING A LATENT IMAGE IN A PHOTOGRAPHIC ELEMENT. AN AQUEOUS ALKALINE DEVELOPER CONTAINING, FOR INSTANCE, ANHYDRO DIHYDRO PIPERIDINO HEXOSE REDUCTONE PROVIDES IMPROVED PROPERTIES. THE DESCRIBED DEVELOPING AGENTS CAN BE USED IN COMBINATION WITH OTHER SILVER HALIDE DEVELOPING AGENTS.

United States Patent Office 3,672,896 Patented June 27, 1972 3,672,896 PHOTOGRAPHIC COMPOSITION, ELEMENT AND PROCESS Rolf S. Gabrielsen and Ismael A. Olivares, Rochester,

N.Y., assignors to Eastman Kodak Company, Rochester, N.Y. No Drawing. Filed Oct. 2, 1969, Ser. No. 863,339

Int. Cl. G03c 1/42, 5/30 US. Cl. 96-66 HD 16 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention This invention relates to certain reductone photographic silver halide developing agents and to photographic elements, processing compositions, and to processes employing such developing agents. In one of its aspects, it

relates to developer compositions containing certain reductone silver halide developing agents. In another of its aspects, it relates to a method of developing a latent image in a photographic element employing the described reductone silver halide developing agents. 1

Description of the prior art It is well known to develop a latent image in a photographic silver halide element using a silver halide developing agent. Developing agents for this purpose have included, for example, aminophenol developing agents agents and polyhydroxybenzene developing agents. This is described, for example, in The Theory of the Photographic Process by Mees and James, 3rd edition, 1966, pages 278- 311.

It has been desirable to provide developing agents which are sufliciently active to provide desired sensitometric properties within the shortest development time and also result in colorless or low-colored oxidation products. Developing agents which provide colorless or low-colored oxidation products are especially desirable in photographic systems in which the oxidation products are not to be removed from the system, such as in systems in which usual washing with water is avoided.

Certain reductone compounds have been used as developing agents, such as piperidino hexose reductone, as described, for example, in US. Pat. 2,936,308 of Hodge, issued May 10, 1960 and US. Pat 2,691,589 of Henn et al. issued Oct. 1-2, 1954. Reductone compounds have also been employed in photographic elements as nucleating agents for direct positive photographic silver halide emulsions as described in US. Pat. 3,347,671 of Salminen issued Oct. 17, 1967.

There has been a continuing need, however, to provide a reductone developing agent which provides desired developing activity, shortened development time, and results in colorless or low-colored oxidation products without loss of desired sensitometric properties. Certain reductone developing agents, as illustrated in comparative Examples 3 and 4 following, do not provide this desired combination of properties.

SUMMARY OF THE INVENTION According to the invention, a combination of desired developing activity, shortened development time, improved stability, colorless or low-colored oxidation products Without loss of desired sensitometric properties is provided in a photographic processing composition, element and/or process employing an anhydro dihydro reductone silver halide developing agent.

DESCRIPTION OF THE PREFERRED EMBODIMENT A wide range of anhydro dihydro reductone silver halide developing agents which provide the described combination of properties, e.g. reduced stain without loss of desired sensitometric properties and improved stability, can be employed according to the invention. These include any anhydro dihydro reductone silver halide developing agents which provide desired developing activity and reduction of stain without adversely affecting desired maximum density, minimum density, photographic speed,

gamma and other desired sensitometric properties. Typically, anhydro dihydro reductone silver halide developing agents which are employed in the practice of the invention are anhydro dihydro amino reductone silver halide developing agents.

A wide variety of anhydro dihydro reductone silver halide devloping agents can be employed in the practice of the invention. Suitable anhydro dihydro reductone silver halide developing agents include, for example, compounds of the formula:

wherein R and R are each hydrogen, alkyl, especially alkyl containing 1 to 5 carbon atoms such as methyl, ethyl, propyl, and pentyl, oratoms completing a heterocyclic nucleus, as denoted by the broken line in Structure I, containing a nitrogen atom, preferably containing 4 to 6 carbon atoms in the nucleus, including, for example, a second nitrogen or an oxygen atom, e.g. morpholino, piperazino, pyrrolidino, hexamethylene imino, piperidino and the like.

Suitable anhydro dihydro reductone silver halide developing agents include:

anhydro dihydro dimethylamino hexose reductone anhydro dihydro diallylamino hexose reductone anhydro dihydro di-n-butylamino hexose reductone anhydro dihydro di-n-hexylamino hexose reductone anhydro dihydro morpholino hexose reductone anhydro dihydro piperazino di(hexose reductone) anhydro dihydro pyrrolidino hexose reductone anhydro dihydro piperidino hexose reductone anhydro dihydro dimethylmorpholino hexose reductone anhydro dihydro methylpiperidino hexose reductone anhydro dihydro N-benzyl-N-methylamino hexose reductone The described anhydro dihydro reductone silver halide developing agents are typically prepared from the corresponding anhydro hexose reductone compounds which in turn are typically prepared from corresponding amino hexose reductones. A typical method of preparing the described amino hexose reductones and anhydro amino hexose reductones is set out in U.S. Pat. 2,936,308 of Hodge issued May 10, 1960. Such compounds are typically prepared from sugars especially'D-glucose although other reducing sugars such as D-galactose, D-fructose, L-sorbose :or. the like can be used. A typical method of preparing thestarting amino hexose reductones comprises heating in areaction medium, substantially free of water, a hexose reducing sugar and an aliphatic or cyclic secondary amine in thepresence of an acidic reductone forming catalytic agent, such as phosphoric acid, boric acid, aceticfaeid, succinic acid or the like. The removal of 3 mols or water results' during the formation of the amino hexose reductone. The. described anhydro amino hexose reductone can be prepared by heating thehydrochloride salts of the amino hexose reductones further in the presence of strong acids such as'sulfuric acid, acetic anhydride, zinc chloride and the like to remove another molzof'water. The des'cribed anhydro dihydro hexose reductone compounds can be prepared fromthe described anhydro amino reductonesby hydrogenation in the presence of a suitable hydrogenation catalyst such'as Raney nickel catalyst. The

'preparatioriof anhydro dihydro piperidino hexose reductone-is typical of the preparation of the class of comfor. about 15 minutes. The resulting mixture is then heated on avsteam bath and stirred until the solution becomes.

hydrogenated in ethanol over a suitable catalyst, such as Raney nickel, to form the desired anhydro dihydro piperidino hexose reductone. The resulting product can be purified if desired such as by recrystallization from a suitablesolvent e.g. ethanol.

The described anhydro dihydro reductone silver halide I developing agents can be employed in the form of a salt, especially an acid salt such as a hydrochloride, sulfate or the like salt. An anhydro dihydro reductone silver halide developing agent as employed herein includes such compounds either in salt form or in their nonsalt form. I

- The described anhydro dihydro reductone silver halide developing agents can be employed'in the practice of the invention in a range of physical locations in a photographic system. They can be employed in one or morelayers of a'photographic element and/or in a processing com i position if desired. The optimum location will depend upon the desired. image, processing conditions and the like. For example, the described anhydro dihydro reductone silver halide developing agents can be employed in a processing composition, such as an aqueous alkaline developer solution or they can be incorporated into one or more layers of a photographic element, such as a photographic silver halide emulsion layer, a layer between the support'and a silver halide emulsion layer, and/or an overcoat layer.-

Accordingly, one embodiment of the invention is' a.

photographic processing composition, especially a silver halide developer, comprising an alkaline development activator and 'an anhydro dihydro reductone silver halide developing agent as described. This is typically anaqueous alkaline solution.

Various development activators can be employed in the practice of the invention. These include any of those which provide the desired activation of the described developing agent. These include, for instance, alkaline development activators, such as inorganic alkalies including, fofrie'x ample, sodium hydroxide, potassium hydroxide, and' lit hv V 4 r r ium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, alkali metal phosphates such as trisodium phosphate, and organic alkaline development activators such as quaternary ammonium bases and salts, e.g. amino alkanols and similar alkaline materials and/ or alkali releasing materials. The described development activators can be applied to "the described photographic element in any suitable manner including, for example,"dipping, spraying and/or suitable surfaceapplication such as with rollers orwith other mechanical a 9 A wide range of concentrations of the described developingagent can be employed in a processing composition in the practice of the invention, depending on the desired image, the developing agent employed, processing conditions; and the like. A" concentration'of about 0.1 mol to about 3.0 mols of developing agent is suitable per liter of processing composition.

Stabilizing the resulting developed image inthe process of the invention can be carried out by contacting the described'photographic',element with a suitable stabilizing agent and typically in an aqueous solution. Nonaqueous solutions can be employed if desired, such as solutions containing ethylene glycol or ethanol. Such a stabilizer solution can be'applied in any suitable manner such as .by

dipping, spraying and/or suitable surface application such as with rollers or withmechanical means.

A wide range of stabilizing agents commonly employed in photographic processing can be employed in the practice of the invention. Typical-stabilizing agents employed in the processing of photographic elements include, for example, ammonium thiocyanate, alkali metal thiocyana'tes; such as sodium thiocyanate and/or potassium thiocy'anateyalkali metal thio'sulfates such as sodium thiosulbleaching. Suitable mercaptoazoles which can be used for this purpose include mercaptoxazoles, mercaptothiazoles, selenazoles, mercaptotetrazoles, and the like-The aqueous solution of stabilizing agent can contain metal salts, e.g. water-solublealuminum and/or chromium salts, such as aluminum sulfate, potassium aluminum sulfate, aluminum chloride, chrome alum, and the like. 7

'I'heti'r'ne for processing a photographic element in the practice of'the invention, that is developing a desired image, can vary over a wide range, typically between a few seconds and several minutes, depending on the desired image, processingconditions and the like.

The conditions for processing can vary over wide ranges. Usually ambient pressures and temperatures of about 20 C(to about 30' C. are suitable but higher temperatures can be employed if desired, such as temperatures .up to aboutC. i

The developing agents employed in the practice ofthe inventioncan be employed in combination with any silver "halide developing agent. The developing agents employed m the practice of the invention canbe employed in such combinationsas auxiliary developing agents or as the main component of the developing combination. Suitable silver halide developing agents which can be employed in combinationvwith the described anhydro dihydro reductone developing agents include, for example, polyhydroxybenzene's such as hydroquinone developing agents, e.g. hydrofqumone', alkyl-substituted hydroquinones, as exemplified by tertiary butyl hydroquinone, methyl hydroquinone and 2,5-dimethyl hydroquinone; catechols and pyrogallol; vchloirb substituted hydroquinones such as chloro hydroquinone or dichloro hydroquinone; alkoxy-substituted hydroquinones such as methoxy hydroquinone or ethoxy hydroquinone; amino phenol developing agents, such as 2,4-diamino phenols and methylamino phenols; ascorbic acid developing acids such as ascorbic acid ketals, and ascorbic acid derivatives such as those described in U.S. Pat. 3,337,- 342 of Green issued Aug. 22 1967; hydroxyamine developing agents such as N,N-di(2-ethoxyethyl) hydroxyl amine; 3-pyrazolidone developing agentssuch as l-phenyl- 3 pyrazolidone and 4-methyl-4-hydroxymethyl-I-phenyl- 3-pyrazolidone, including those described in British 930,- 572 published July 3, 1963; and acyl derivatives of paraamino phenol such as described in British 1,045,303 published Oct. 12, 1966; hydroxy tetronic acid and hydroxy tetronimide developing agents; pyrimidine developing agents; and the lik The developing agents described can be employed for developing an image in a wide range of photographic emulsions. They can be employed in such emulsions if desired. The photogra hic emulsions employed in the practice of the invention can be X-ray or other nonspectrally sensitized emulsions or they can contain spectral sensitizing dyes. The light-sensitive silver halide emulsions employed in the practice can conveniently be ortho sensitized or pan sensitized with spectral sensitizing dyes. For instance, these emulsions can be spectrally sensitized by treating with a solution of a sensitizing dye in an organic solvent or the dye may be added in the form of a dispersion, such as described in Owens et al. French 1,482,774. Spectral sensitizing dyes useful in sensitizing such emulsions are described, for example, in U.S. Pat. 2,526,632 of Brooker and White of Oct. 24, 1950; 2,503,776 of Sprague issued Apr. 11, 1950; 2,493,748 of Brooker et al. issued Jan. 10, 1950; and 3,384,486 of Taber et al. issued May 21, 1968. Spectral sensitizers which can be used include the cyanines, merocyanines, complex (trinuclear) cyanines, complex (trinuclear) merocyanines, styryls and hemicyanines. The cyanines can contain such basic nuclei as thiazoles, oxazoles, selenazoles, and imidazoles. Such nuclei may contain sulfoalkyl; carboxyalkyl; and alkyl amino groups and may be fused to benzene or naphthalene rings either unsubstituted or substituted with halogen, phenyl, alkyl or alkoxy groups. The dyes can be symmetrical or unsymmetrical and may contain alkyl, phenyl, or heterocyclic substituents on the polymethine chain. The merocyanine dyes can contain the basic nuclei mentioned above as well as acid nuclei such as thiohydantoins, rhodanines, oxazolidenediones, and barbituric acids. The acid nuclei can be substituted with alkyl groups, phenyl groups, carboxy, sulfo or amino groups. The emulsions can contain supersensitizing dye combinations such as those described in U.S. Pat. 2,739,964 of Brooker et al. issued Mar. 27, 1956; U.S. Pat. 2,688,545 of Carroll et al. issued Sept. 7, 1954; U.S. Pat. 2,701,198 of Carroll et al. issued Feb. 1, 1955; U.S. Pat 2,739,149 of Van Lare issued Mar. 20, 1956; Fuji British 1,128,840 or the emulsions can be supersensitized with ascorbic derivatives, azaindenes, cadmium salts and organic sulfonic acids as described in U.S. Pat. 2,933,390 of McFall et al. issued Apr. 19, 1960 and U.S. Pat. 2,937,089 of Jones et al. issued May 17, 1960.

The silver halide emulsions used in the practice of the invention can comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. The emulsions can be coarse or fine grained and can be prepared by any of the well-known procedures in emulsion making, e.g. single jet emulsions, double jet' emulsions, such as Lippman emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions, such as those described in U.S. Pat. 2,222,264 of Nietz et al. issued Nov. 19, 1940; U.S. Pat. 3,320,069 of Illingsworth issued May 15, 1967 and U.S. Pat. 3,271,157 of McBride issued Sept. 6, 1966. Surface image emulsions can be used or internal image emulsions such as those described in U.S. Pat. 2,592,250 of Davey et al. issued Apr. 8, 1952; U.S. Pat. 3,206,313 of Lowe et al. issued Sept. 14, 1965; U.S. Pat. 3,367,778 of Berriman et al. issued Feb. 6, 1968;

and Belgian Pat. 704,255. If desired, mixturesofsurface and internal image emulsions can be used as described in U.S. Pat. 2,996,382 of Luckey et al. issued Aug. 15,

1961. Negative type emulsions can be used or direct posi tive emulsions such as those described in U.S. Pat. 2,184,- 013 of Lee rma-kers issued Dec. 19, 1939; U.S. Pat. 2,541,- 472 of Kendall et al. issued Feb. 13, 1951; U.S. Pat. 3,367,778 of Berriman et al. issued Feb. 6, 1968; British Pat. 723,019; French Pat. 1,520,821; U.S. Pat. 2,563,785 of Ives issued Aug. 7, 1951; U.S. Pat. 2,456,953 of Knott et al. issued Dec. 21, 1968; and U.S. Pat. 2,861,885 of Land issued Nov. 25, 1958.

The silver halide emulsions employed in the practice of the invention can be unwashed or washed to remove soluble salts. In the latter case the soluble salts can be removed by chill setting and bleaching or the emulsion can be coagulation washed.

The silver halide emulsions employed inth'e practice of the invention can be sensitized with chemical sensitizers, such as with reducing agents; silver, selenium, or tellurium compounds; gold, platinum or palladium compounds; or combinations of these. Suitable procedures are described, for example, in U.S. Pat. 1,623,499 of Sheppard issued Apr. 5, 1927; U.S. Pat. 2,399,083 of Waller et al. issued Apr. 23, 1946; U.S. Pat. 3,297,447 of McVeigh issued J an. 10, 1967; and U.S. Pat. 3,297,446 of Dunn issued Jan. 10, 1967.

The silver halide emulsions employed in the practice of the invention can contain speed increasing compounds such as polyalkylene glycols, cationic surfactants and thioethers or combinations of these as described, e.g. in U.S. Pat. 2,886,437 of Piper issued May 12, 1959; U.S. Pat. 3,046,134 of Dann et al. issued July 24, 1962; U.S. Pat. 2,944,900 of Carroll et al. issued July 12, 1960; and U.S. Pat. 3,294,540 of Gotfe issued Dec. 27, 1966.

The described silver halide emulsions employed in the practice of the invention can be protected against the production of fog and can be stabilized against loss of sensitivity during keeping. Suitable antifoggants and stabilizers each used alone or in combination include, for example, thiazolium salts; azaindenes; mercury salts as described, for example, in U.S. Pat. 2,728,663 of Allen et al. issued Dec. 27, 1955; urazoles; sulfo catechols; oximes described, for example, in British Pat. 623,448; nitron; nitroindazoles; mercaptotetrazoles; polyvalent metal salts described, e.g. in U.S. Pat. 2,839,405 of Jones issued June 17, 1958; palladium, platinum and gold salts described, for example, in U.S. Pat. 2,566,263 of Trivelli et al. issued Aug. 28, 1951 and U.S. Pat. 2,597,915 of Yutzy et al. issued May 27, 1952.

The photographic and other hardenable layers of a photographic element used in the practice of this invention can be hardened by various organic or inorganic hardeners, alone or in combination, such as aldehyde hardeners and blocked aldehydes, ketones, carboxylic and carbonic acid derivatives, sulfonate esters, sulfonyl halides and vinyl sulfones, active halogen compounds, epoxy compounds, aziridines, active olefins, isocyanates, carbodiimides, mixed function hardeners and polymeric hardeners such as oxidized polysaccharides such as dialdehyde starch and oxyguar gum and the like.

Photographic element and emulsions described in the practice of the invention can contain various colloids alone or in combination as vehicles, binding agents and in various layers. Suitable hydrophilic materials include both naturally occurring substances such as proteins, for example, gelatin, gelatin derivatives, cellulose derivatives, polysaccharides such as dextran, gum arabic, and the like; and synthetic polymeric substances such as water-soluble polyvinyl compounds like poly(vinyl pyrrolidone), acrylamide polymers and the like.

The described photographic emulsion layers and other layers of the photographic element employed in the practice of the invention can also contain alone or in combination with hydrophilic, water-permeable colloids, other synthetic polymeric compounds such as dispersed vinyl compounds such as in latex form and particularly those which increase the dimensional stability of the photographic materials. Suitable synthetic polymers include those described in U.S. Pat. 3,142,586 of Nottorf issued July 28, 1964; U.S. Pat. 3,193,386 of White issued July 6, 1965; U.S. Pat. 3,062,674 of Houck, Smith and Yudelson issued Nov. 6, 1962; U.S. Pat. 3,220,844 of- Houck,

Smith and Yudelson issued Nov. 30, 1965; U.S.Pat.

3,287,289 of Ream and Fowler issued Nov. 22, 19 66 and U.S. Pat. 3,411,911 of Dykstra issued Nov. 19, 1968. Particularly efiective are those water-insoluble polymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates,v and those which "have crosslinking sites which facilitate hardening or curing as bonate film and related films or resinous'materials, as

well as glass, paper, metal and the like. Typically a flexible support is employed, especially a paper support which can be partially acetylated or coated withbaryta and/or an alpha-olefin polymer, particularly a polymer of an alpha-olefin containing 2-10 carbon atoms such as polyethylene, polypropylene, ethylene-butene copolymers and the like.

The photographic elements employed in the practice of the invention can contain plasticizers and '1ubr1cants, such as polyalcohols, glycerin and diols as describe hfor example, in U.S. Pat. 2,960,404 of Tirnmons et al. issued Nov. 15, 1960; fatty acids or esters such as descnbed in U.S. Pat. 2,588,765 of Robjins issued Mar. 11, 19 52; and U.S. Pat. 3,121,160 of Duane issued Feb. 11, 1964; and silicone resins such as those described in British Pat. 955,061. I

The photographic elements employed inthe practice of the invention can contain surfactants such as sapomn, anionic compounds, such as alkyl aryl sulfonates described, for example, in U.S. Pat. 2,600,831 of Baldsiefen issued June 17, 1952 and amphoteric compounds such as those described in U.S. Pat. 3,133,81601 ,Ben-

Ezra issued May 19, 1964.

The photographic elements employed in the presence of the invention can contain matting agents "such as starch, titanium dioxide, zinc oxide, silica, polymeric beads including beads described, for example, in U.S. Pat. 2,992,101 of Jelley et al. issued luly'll, 1961 and U.S. Pat. 2,701,245 of Lynn issued Feb- 1, 1955. p

The described photographic elements employed in the practice of the invention can also contain a brightening agent including stilbene, triazine, oxazole and coumarm brightening agents. Water-soluble brighteners such as those described in German Pat. 972,067 and Pat. 2,933,390 of McFall et al. issued Apr. 19, 19 60 or'dispersions of brighteners can be used such as those described in German Pat. 1,150,274 and U.S. Pat. 3,406,070 of Oetiger et al. issued Oct. 15, 1968. v I

The sensitizing dyes, developing agents and other addenda employed in the practice of the invention can be added to an emulsion employed in the practice of the invention from water solutions or suitable organic solvent solutions. The compounds can be added using various procedures including those described in U.S. Pat. 2,912,343 of Collinset al. issued Nov. 10, 1959; US. Pat. 3,342,605 of McCrossen et al. issued Sept.

19, 1967; U.S. Pat. 2,996,287 of Audran issued Aug.,

15, 1961; U.S. Pat. 3,425,835 of Johnson et al. issued Feb. 4, 1969. v

The described developing agents employed in the practice of the invention can be used with elements designed for color photography, for example, ,eleme'nts containing color forming couplers such as those described in U.S. Pat. 2,376,679 of Frohlich et al. issuedMay 22, 1945; U.S. Pat. 2,322,027 of Jelley et al. issued June 15, 1943; U.S. Pat. 2,801,171 of Fierke et alissued July 30, 1957; U.S. Pat. 2,698,794 of Godowsky issued Jan. 4, 1955; U.S. Pat. 3,227,554 of Barr et al. issued Jan. 4, 1966; and U.S. Pat. 3,046,129 of Grahamet al. issued July 24, 1962; or elements to be developed in solutions containing couplers such as those described in U.S. Pat. 2,252,718 of Mannes and Godowskylissued Aug. 19, 1941; U.S. Pat. 2,592,243 of Carroll et al. issued Apr. 8, 1952 and U.S. Pat. 2,950,970 ofSchwan et al. Aug. 30, 1960. The described developing agents in the practicegof the invention can be employed for processing photographic elements by. various methodsin cluding processing in alkaline solutions containing conventional fdeveloping agents as described; web processing such -as. described in U.S. Pat. 3,179,517 of Tregillusetal-1 is ued Apr. 20, 1965; stabilization processin as described, vfor example, in Yackel et al. Stabilization Processing'rof Films and Papers, PSA Journal, vol. 16B; August1950; monobath processing as described in Levy conibin erl Development and "Fixation of Photographic Images Monobathsf Photographic Science andjEngir'ieering, vol. 2, No. 3, October 1958, and U.S.Pat'. 3,392,019 of Barnes et al. issued July 9, 1968.*If des ire'd, the'photographic elements employed in the practice of the ji nvfgmtion can be processed in hardening developers sucliips those described in U.S. Pat. 3,232,761'01 Allerret al. issued Feb. 1, 1966; in roller transport processors such as those described in s. Pat. 3,025,179 or Russell-ct al. issuedMar. 20, '1962; or by surface application processing as described in U.S. Pat. 3,418,132 of Kitze issued Dec. 24, 1968. I Another embodiment of the invention accordingly is a photographic silver salt emulsion comprising a photographic silver salt and an anhydro dihydro hexose reductone silver halide developing agent as described. A'further embodiment of the invention is a photographic element comprising a support, a photographic silver salt and an anhydro dihydro reductone"'silver halide developing agent as described 9 '1 When an anhydro dihydro re'ducton'e silver halide developing agent accordingto the'practi'ce of the inventionis employed in a photographic element," a 'concentration of about 0.1 to 4.0 mols ofdeveloping agent pg; mol'of silver present in the" element-"is" usually suita e. The described reductions can be employed in the photographic process comprising developing a latent image "in an exposed photographic silver saltin the presence of a silver halide developing agent wherein the improvement comprises employing an anhydro dihydro'reductone silver halide developing agent as the described'developing agent. Such a process can comprise developingthe latent image in the presence of an auxiliary silver halide developing agent as described.

A photographic process according'to the 'invent ion'ca'n also comprise developing a latent image in a photographic silvers'alt in a photographic element containingan-an- I hydro dihydro reduct'one" silver halide developing agent by contacting the photographicelementwithan alkaline development-activator.

The following-examples are included for a further understanding'of the invention. P a

'EXAMPLE 1 employed in the. photographic art to provide a series of steps of increasing exposure. The resulting latent image is developed by immersing the strip of film at 20 C. in a silver halide developer having the following components:

Mol Developing agent 0.02 Sodium sulfite 0.20 Sodium carbonate 0.20

Water to 1 liter.

Anhydro dihydro piperidino hexose reductone is employed as the developing agent. The developer has a pH of 10.0. The strip of film is immersed in the developer until an image is developed having a density of 2.0 in the fourth step of the strip of film. This requires 2.6

minutes (156 seconds). The film contains no observable Time of development,

Example Developing agent minutes 2 Hydroquinone (prior art) 12.5 3 Piperidino hexose reductone (prior art), 7.9 4 Anhydro piperidino hexose reductone-.. 3. 9

The resulting strip of film for Example 2 contains significant oxidation stain. This illustrates the surprisingly reduced development time provided by a developing agent of the invention, without undesired oxidation products and without loss of desired sensitometric properties over closely relating developing agents.

EXAMPLE 5 The procedure set out in Example -1 is repeated with the exception that sodium carbonate in the described developer is replaced with trisodium phosphate and the pH of the developer is 11.5. The strip of film is immersed in the developer until an image is developed having a density of 2.0 in the fourth step of the sensitometric strip of film. This required 1.5 minutes (90 seconds).

EXAMPLE 6 This illustrates the use of a combination of developing agents in the practice of the invention.

A strip of fine grain silver bromoiodide positive film having 363 milligrams of silver per square foot and 1080 milligrams of gelatin per square foot is sensitometrically exposed through a step wedge and the resulting latent image is developed by immersing the strip of film at 20 C. in a silver halide developer having the following composition:

Mol

Hydroquinone 0.02 Sodium sulfite 0.20 Trisodium phosphate 0.20

Anhydro dihydro piperidino hexose reductone 0.02 Water to 1 liter.

The developer has a pH of 11.5. The strip of film is immersed in the developer until an image is developed having a density of 2.0 in the fourth step of the film. This requires 0.90 minute (54 seconds).

EXAMPLES 710 Twenty milligrams of a developing agent is placed in a 10 ml. beaker. And .1 ml. of an aqueous solution of sodium hydroxide containing 4% by weight sodium hydroxide is added. The resulting mixture is stirred to dissolve the developing agent. The solution is allowed to stand five minutes. The solution is then absorbed into a piece of chromatographic paper 1% inches by 2 inches (Whatman 3MM chromatographic paper). The piece of paper is then held over water in a jar for 24 hours at about 20 C. The paper is then removed from the jar and dried. The color of the paper is read on a densitometer to neutral transmitted light compared to a piece of untreated paper. The density of the untreated paper is substracted from the density of the treated paper to give a figure which is designated as net stain.

The net stain provided by difierent developing agents is set out in the following table:

This illustrates reduced stain provided by a silver halide developing agent of the invention.

EXAMPLES 11-14 A silver halide developer is prepared by mixing the following components:

Mol Developing agent 0.02 Sodium sulfite 0.20

Trisodium phosphate 0.20 Water to 1 liter.

The developer has a pH of 11.5. A strip of fine grain silver bromoiodide positive film having 363 milligrams of silver per square foot and 1080 milligrams of gelatin per square foot is sensitometrically exposed through a step wedge and the resulting latent image is developed by immersing the strip of film at 20 C. in the described silver halide developer until an image is developed having a density of 2.0 in the fourth step of the strip of film.

Employing this procedure each of the developing agents given in the following table provides a density of 2.00 although the time required to obtain this density is significantly shorter when anhydro dihydro piperidino hexose reductone is employed as the developing agent.

The procedure is then repeated with the exception that the developer is held on a steam bath for 24 hours at about C. before the exposed strip of film is immersed in the developer. The strip of film is held in the developer for the same time as is required to develop an image to a density of 2.00. The resulting density is designated as density after incubation. This is given in the following table also.

This demonstrates that a developing agent of the invention provides surprisingly increased stability.

EXAMPLES 15-19 Similar results as set out in Example 1 are obtained employing the following developing agents in place of anhydro dihydro piperidino hexose reductone:

EXAMPLE 15 Anhydro dihydro dimethylamino hexose reductone.

Anhydro dihydro 1 1 EXAMPLE 16 Arhq qsra hi q e i sn r by coating P p support with a gelatin coating containing 20 milligrams P r. squa .fQQtEt tq y y y -p y 3-pyrazolidone, 45 milligrams per square foot of anhydro dihydro piperidino hexose reductone and 430 milligrams per square'foot of'gelatin. Over this is coated a photographic silver chloroiodide' emulsion containing 30 milligrams per squarefootof silver and 120 milligramsuper ,square foot of gelatin. The resulting photographic element is sensitornetrically exposed and an image is developed by immersing the element an activator:

Mol sulfite v I 0.20 Trisodium phosphate 0.20 'Water to 1 liter.

The activator is adjusted to a pH of 11.5. A developed image results having good maximum density.

' EXAMPLE 21 :This illustrates preparation of anhydro dihydro piperidino hexose reductone.

One mol of anhydrous D-glucose and 1.3 mols of piperidine are stirred together in 100 ml. of absolute ethanol under nitrogen for about 15 minutes. The resulting mixture is then heated on a steam bath and stirred until the solution is homogeneous. A solution of glacial acetic acid in absolute ethanol is added dropwise to theflresulting solution with stirring at reflux temperature under nitrogen'for 12 hours. The mixture is then cooled to room temperature, i.e. about 20 C. and the resultingcrystals of piperidino hexose reductone are filtered, washed with ethanol and recrystallized from ethanol.

The piperidino hexose reductone is dehydrated by adding the compound to a butanol solution of anhydrous hydrogen chloride. The mixture is stirred reaction completion to form the desired anhydro piperidino hexose reductone hydrochloride. The hydrochloride is neutralized 1 to the free base, filtered, and added to ethanol.

The resulting mixture is then hydrogenated in the presence of Raney nickel catalyst until reaction con 1jpletion. The resulting desired anhydro dihydro piper dino hexose reductone is separated, recrystallized from ethyl acetate and identified by infrared analysis.

EXAMPLE 22 The procedure set out in Example 21 is repeated with the exception that dimethylamine is employed in place of piperidine as a starting material. Anhydro dihydro dimethylamino hexose reductone is produced.

EXAMPLE 23 is produced.

EXAMPLE 24 The procedureset out in Example 21 is repeated with the exception that pyrrolidine is employed as a starting material in place of piperidine, and triethylamine is used as a solvent.

12 Anhydro dihydro pyrrolidine hexose reductone is produced.

EXAMPLE 25 The procedure set out in Example 21 is repeated with the exception that morpholine is employed in place of piperidine as a starting material.

Anhydro dihydro morpholino hexose reductone is produced.

EXAMPLES 26-28 Similar results as set out in Example 1 arefobtained employing the following developing agents vinplace of anhydro dihydro piperidino hexose reductone:

. EXAMPLE 6 Anhydro dihydro pyrrolidino hexose reductone.

EXAMPLE 27 Anhydro dihydro hexamethyleneimino hexose-reductone.- EXAM'PIJE 2 8 Anhydro dihydro 4-methylpiperidino hexose reductone. The invention, has been described in detail with partic- .ular reference, to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit andscope of the invention. We claim: .1. A photographic processing composition comprising an alkaline development activator and an anhydro dihydro reductone silver halide developing agent. i

2. A photographic processing composition as in claim 1 comprising an aqueous alkaline solution.

'3. A photographic processing composition as in claim 1 wherein said anhydro dihydro reductone silver halide developing agent is a compound of'theformula:

wherein R and R, are eachihy'drogen, allrylcontaining 1 1 wherein said anhydro dihydro reductone'silver halide developing agent is anhydro dihydro piperadino hexose reductone, anhydro dihydropyrrolidino hexose reductone, or anhydro d ihydro dimethylamino hexosereductone.

5. A photographic processing composition as iniclaim 1 comprising an. auxiliary silver halide developing agent. 6. A photographic. silver salt emulsion comprisinga photographic silver salt and an anhydro dihydro hexose reductone silver halide developing agent. I

7. A photographic silver salt emulsion as in clainio wherein saidphotographic silver salt is a photographic silver halide.

v 8. A photographic element comprising a support, a photographic silver salt and an anhydro dihydro reductone silver halide developing agent. i A i v j claim 8 wherein' said anhydro dihydro reductone silver halide developing agent is a compound of the formula: i p

.wherein R and R areeachhydrogenpallryl containing 1 to 5 carbonv atoms,

or atoms completing a heterocyclic nucleus. e

10. A photographic element as in claim 8 wherein said anhydro dihydro reductone silver halide developing agent is anhydro dihydro piperidino hexose reductone, anhydro dihydro pyrrolidino hexose reductone, or anhydro dihydro dimethylamino hexose reductone.

11. A photographic element as in claim 8 comprising an auxiliary silver halide developing agent.

12. A photographic element as in claim 8 comprising a 3-pyrazolidone silver halide developing agent.

13. In a photographic process comprising developing a latent image in an exposed photographic silver salt in the presence of a silver halide developing agent, the improvement comprising employing an anhydro dihydro reductone silver halide developing agent as said developing agent.

14. A photographic process as in claim 13 comprising developing said latent image in the presence of an auxiliary silver halide developing agent.

15. A process as in claim 14 wherein said auxiliary silver halidedeveloping agent is a 3-pyrazolidone silver halide developing agent.

References Cited UNITED STATES PATENTS 2,691,589 10/1954 Henn et al 9666.1 2,936,308 5/1960 Hodge 96-664 X 3,266,894 8/ 1966 Weyerts et al 9666 X 3,347,671 10/ 1967 Salminene 963 3,380,828 4/1968 Kitze et a1 9666 X HAROLD ANSHER, Primary Examiner US. Cl. X.R.

96663; 2602ll R 

